Marine exhaust system

ABSTRACT

An exhaust assembly comprising inner and outer concentrically arranged flexible conductors held in concentric relation by spacers and fittings at the opposite ends, the fitting at one end being adapted to connect the inner and outer conductors, respectively, to the manifold of an engine and to a coolant pump and the fitting at the other end being adapted to connect the inner and outer conductors, respectively, to a muffler and to an overboard line.

United States Patent [1 1 Plank, Jr. et al.

[ Apr. 9, 1974 1 MARINE EXHAUST SYSTEM [75] Inventors: John Lee Plank, Jr., Leominster;

Thomas J. Kilcoyne, Clinton, both of Mass.

[73] Assignee: National Perforating Corporation,

Clinton, Mass.

22 Filed: Dec. 29, 1971 21 Appl. No.: 213,521

[52] US. Cl 165/51, 29/157.3, 60/320,

138/111,165/71,165/133,165/154, 285/41 [51] Int. Cl. F0ln 3/04 58 Field of Search 60/320-321;

165/154-156, 71, 51; 138/113-114, 148, 108, DIG. 3; 285/41, 133 R, 138; 29/1573 [5 6] References Cited UNITED STATES PATENTS 3,105,708 10/1963 Esty 285/41 3,126,918 3/1964 Eaton.....

2,787,289 4/1957 Press 138/D1G. 3

3,540,486 11/1970 Flounders 138/125 2,683,592 7/1954 Birney 165/71 X FOREIGN PATENTS OR APPLICATIONS 28,885 12/1896 Great Britain 138/148 1,059,847 11/1953 France 285/133 R Primary Examiner-Albert W. Davis, Jr.

Assistant ExaminerS. J. Richter Attorney, Agent, or FirmDike, Bronstein, Roberts & Cushman [5 7] ABSTRACT An exhaust assembly comprising inner and outer concentrically arranged flexible conductors held in concentric relation by spacers and fittings at the opposite ends, the fitting at one end being adapted to connect the inner and outer conductors, respectively, to the manifold of an engine and to a coolant pump and the fitting at the other end being adapted to connect the inner and outer conductors, respectively, to a muffler and to an overboard line. 1

1 Claim, 4 Drawing Figures MARINE EXHAUST SYSTEM BACKGROUND OF THE INVENTION Fl exiblejac keted conductors for carrying off exhaust N ""ga'sesi'r'' disclosed in such U.S. Pats. as Esty, No.

3,105,708, Willy, No. 3,379,277, Gara, No. 1,478,948, Thompson, No. 2,935,039, Larsen, No. 3,198,162 and Moffitt, No. 799,013. However, none of the patents disclose structure which is adequately designed for easy installation in boat hulls nor a structure designed to provide adequate resistance to the effects of salt water corrosion and the destructive effects of hot exhaust gases. It is the purpose of this invention to provide a structure which in contrast to those shown in the foregoing patents is designed to be adapted to boat hulls of different size without prefabrication to size, a structure which is easy to install in, around, above and under bulkheads, stanchions, and the like without substantial alteration of the hull, a structure which is completely safe in so far as containing the hot gases and preventing the crew or occupants from coming in contact with hot surfaces, and a structure which provides for troublefree, substantially life-long use in that it is substantially completely resistant to the corrosive effects of salt water and to hot exhaust gases.

SUMMARY An exhaust assembly for discharging exhaust gases from a marine engine comprising concentrically disposed inner and outer conductors defining a central passage adapted to be connected to the exhaust manifold of the engine and a surrounding annular passage adapted to be connected to a coolant pump, and means supporting the inner conductor in concentric relation with the outer conductor, said means comprising longitudinally spaced fluted rings disposed about the inner conductor within the annular passage with the flutes alternately disposed toward the outer surface of the inner conductor and the inner surface of the outer conductor, said flutes providing spacers which permit uninterrupted flow of coolant through said annular passage. The inner conductor is comprised of braided metal wire lined with Teflon and the'outer conductor is comprised of Neoprene. The spacer rings are comprised of stainless steel and are sprung onto the other conductors so as to maintain their longitudinal spacing thereon and there is a clearance of a predetermined amount between the apices of the outwardly disposed flutes and the inner surfaces of the outer conductor of approximately 1/ l 6 of an inch. There are fittings adapted to be connected to the inner and outer conductors at the opposite ends, each comprising a rigid pipe length having at one end a threaded portion and at the other end reduced portion for receiving the end of the inner conductor, and a jacket intermediate the ends adapted to receive an end of the outer conductor. The pipe and jacket comprise a continuation of the annular passage between. the inner and outer conductors, rigidly supporting the inner and outer conductors in concentric relation at said ends, and a conductor is connected to the jacket at one end for supplying coolant to the annular passage and to the jacket at the other end for discharging the coolant.

The invention will now be described in greater detail with reference to the accompanying drawings wherein:

FIG. 1 is a view, partly in elevation and partly in section, showing the component parts of the structure of this invention;

FIG. 2 is a diametrical section;

FIG. 3 is a view, partly in section and partly in elevation, of the fitting for connecting the inner and outer conductors to the engine manifold and to a coolant pump; and

FIG. 4 is a similar view showing the fitting for connecting the inner and outer conductors to the muffler and to an overboard line.

Referring to FIGS. 1 and 2, the assembly comprises concentrically disposed inner and outer flexible conductors 10 and 12 defining a central passage 14 adapted to be connected to the exhaust manifold of an engine and a surrounding annular passage 16 adapted to be connected to a coolant pump.

The outer conductor 12 is of corrugated construction comprised of heavy duty industrial design reinforced Neoprene.

The inner conductor 10 is comprised of a reinforced stainless steel braided mesh 18 lined with a thermally tolerant Teflon 20.

I The outer and inner conductors are held in'concentric relation by means of annular spacers 22 comprised of stainless steel, each spacer being of fluted construction. The fluted spacers 22 are constructed so that the locus of the inner apices 22a comprise a cylinder slightly smaller in diameter than the outside diameter of the inner conductor 10 and the locus of the outer apices 22b define a cylinder whose diameter is slightly less than the inside diameter of the outer conductor 12. As thus constructed, the spacers are sprung onto the inner conductor 10 so that they will have frictional engagement with the outer surface and so that they can be disposed at uniformly spaced intervals therealong and remain in said positions. When so disposed on the inner conductor the apices at the outer side are spaced from the inner surface of the outer conductor thus allowing for freedom of flexibility while providing for holding the conductors substantially concentric throughout their length. The channels between the flutes both inside and outside provide for free flow of the coolant in the annular space 16. A clearance of approximately 1/16 of an inch is desirable between the outer apices and the inside of the outer conductor.

The exhaust assembly as thus made up is adapted to be supplied in continuous lengths and can be easily assembled for a specific installation by means of fittings 28 and 30 (FIGS. 3 4) designed, respectively, to connect one end of the assembly to the manifold of the engine and a coolant pump and the other end to a muffler and outboard line.

The fitting 28 comprises a rigid pipe 32 provided at one end with threads 34 for attachment to the manifold of the engine and provided at its other end with a reduced portion 36 corresponding substantially in diameter to the inside diameter of the inner conductor over which the end of the inner conductor is telescopically engaged. A skirt 38 is welded or otherwise fastened to the pipe adjacent the reduced portion, having an inside diameter corresponding substantially to the outside diameter of the inner conductor for telescopically receiving the end of the inner conductor. Sealing means may be employed between the telescoping surfaces of the inner conductor, the reduced portion of the pipe and the skirt, or the skirt may be swaged to pinch the end of the conductor on the reduced portion. A jacket 40 is mounted on the pipe intermediate its ends by welding or otherwise which has an outside diameter corresponding substantially to the inside diameter of the outer conductor over which the end of the outer conductor is telescopically engaged and secured by means of a suitable sealant. The pipe and jacket provide a continuation of the annular space between the inner and outer conductors and a conductor tube 42 provides for supplying coolant to the jacket.

Both the pipe 32 and the jacket 40 are provided with drain cocks or valves 44 and 48 respectively. These drain cocks or valves may comprise simply a threaded opening into which is screwed a threaded drain plug. Desirably, a deflector 50 is welded to the pipe within the jacket opposite the conductor 42 to prevent cavitation.

The fitting 30 is similar to that of the fitting 28 comprising a rigid pipe 50 threaded at 52 at one end for connection to a muffler. The other end of the pipe has a reduced portion 54 over which the end of the inner conductor is telescoped and a skirt 56 within which the end of the inner conductor is telescoped. The pipe 50 has also a jacket 58 for telescopically receiving the end of the outer conductor 12. A conductor 60 connected to the jacket provides for discharge of the coolant from the annular space 16. Although not shown, if desired, drain plugs may be provided in the pipe 50 and jacket 58 as were provided in the fitting 28.

The assembly herein illustrated is especially designed for marine installation since it is perfectly flexible and can be fitted to any size vessel by the simple expedient of cutting appropriate lengths of conductors and assembling the fittings therewith without welding. Because of the flexibility of the assembly it can be fitted to any hull, around, over, under or through bulkheads, stanchions and the like, with the least amount of alteration of the interior. The only limitation is that the conductors must proceed upwardly from the engine to the muffler. The jacketing minimizes accidental burning by crew or passengers. The stainless steel exterior of the inner conductor resists the corrosive effects of sea water and the Teflon-coated interior is impervious to the corrosion from the exhaust gases.

lt should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all modifications and equivalents falling within the scope of the appended claims.

I claim:

1. An exhaust assembly comprising a flexible exhaust conduit, said conduit comprising a braided stainless steel tube containing an impervious lining of thermally tolerant teflon coextensive with its inner surface, said conduit being perfectly smooth and of uniform inside and outside diameter, a pair of coupling pipes connected one to each of the respective ends of the con- 4 duit by telescoping sliding interengagement with said ends, said conduit and coupling pipes providing a continuous passage for the flow of exhaust gases therethrough, each pipe having ends and at one end a smooth cylindrical portion of reduced diameter slidingly received within an end of the conduit, by means of which the pipes are connected to the ends of the conduit, and a smooth flange around each cylindrical portion forming therewith a circular groove within which the ends of the conduit are slidingly received to seal said ends, a jacket member mounted concentrically on and rigidly secured to each pipe, said jacket members being of circular cross-section and larger in diameter than the pipe so as to provide an annular chamber about the pipe, said jacket members having open and closed ends with the open end facing in the direction of said portion of reduced diameter and said open ends of the jacket members at the opposite ends of the conduit confronting each other, a flexible jacket tube comprised of reinforced neoprene of larger diameter than the conduit mounted about the conduit in concentric relation thereto, said jacket tube having end portions slidingly engaged over the open ends of the jacket members and intermediate its ends longitudinally spaced peripheral corrugations, said jacket tube surrounding the conduit and providing an annular passage about the conduit which is in communication with the jacket members through which cooling fluid can flow from one jacket member to the other, said jacket members containing ports, the port in one jacket member providing for in-flow of a coolant fluid into the jacket tube and the port in the other jacket member providing for discharge of the coolant fluid from the jacket tube, and spacing means mounted on the conduit within the annular space between it and the jacket tube for supporting the conduit within the jacket tube in substantially concentric relation threto comprising a plurality of annular collars disposed about the conduit at longitudinally spaced intervals along the conduit, each collar being relatively narrow in width and embodying corrugations widthwise thereof providing inwardly and outwardly extending peaks between which there are open passages, the inwardly extending peaks being frictionally engaged with the conduit and resisting longitudinal displacement of the collars along the conduit, and the outwardly extending peaks extending outwardly from the conduit to approximately onesixteenth of an inch from the inner side of the jacket tube such that there is a clearance between the outer ends of the peaks and the jacket tube, and said passages between the corrugations providing for free unobstructed flow of the coolant, and wherein the component parts of the assembly are constructed and arranged to be assembled and installed in situ. 

1. An exhaust assembly comprising a flexible exhaust conduit, said conduit comprising a braided stainless steel tube containing an impervious lining of thermally tolerant teflon coextensive with its inner surface, said conduit being perfectly smooth and of uniform inside and outside diameter, a pair of coupling pipes connected one to each of the respective ends of the conduit by telescoping sliding interengagement with said ends, said conduit and coupling pipes providing a continuous passage for the flow of exhaust gases therethrough, each pipe having ends and at one end a smooth cylindrical portion of reduced diameter slidingly received within an end of the conduit, by means of which the pipes are connected to the ends of the conduit, and a smooth flange around each cylindrical portion forming therewith a circular groove within which the ends of the conduit are slidingly received to seal said ends, a jacket member mounted concentrically on and rigidly secured to each pipe, said jacket members being of circular cross-section and larger in diameter than the pipe so as to provide an annular chamber about the pipe, said jacket members having open and closed ends with the open end facing in the direction of said portion of reduced diameter and said open ends of the jacket members at the opposite ends of the conduit confronting each other, a flexible jacket tube comprised of reinforced neoprene of larger diameter than the conduit mounted about the conduit in concentric relation thereto, said jacket tube having end portions slidingly engaged over the open ends of the jacket members and intermediate its ends longitudinally spaced peripheral corrugations, said jacket tube surrounding the conduit and providing an annular passage about the conduit which is in communication with the jacket members through which cooling fluid can flow from one jacket member to the other, said jacket members containing ports, the port in one jacket member providing for in-flow of a coolant fluid into the jacket tube and the port in the other jacket member providing for discharge of the coolant fluid from the jacket tube, and spacing means mounted on the conduit within the annular space between it and the jacket tube for supporting the conduit within the jacket tube in substantially concentric relation thereto comprising a plurality of annular collars disposed about the conduit at longitudinally spaced intervals along the conduit, each collar being relatively narrow in width and embodying corrugations widthwise thereof providing inwardly and outwardly extending peaks between which there are open passages, the inwardly extending peaks being frictionally engaged with the conduit and resisting longitudinal displacement of the collars along the conduit, and the outwardly extending peaks extending outwardly from the conduit to approximately one-sixteenth of an inch from the inner side of the jacket tube such that there is a clearance between the outer ends of the peaks and the jacket tube, and said passages between the corrugations providing for free unobstructed flow of the coolant, and wherein the component parts of the assembly are constructed and arranged to be assembled and installed in situ. 